Pharmacology Flashcards
What is the first line of therapy used in treatment of GERD, Peptic Ulcer diseases and Zollinger- Ellison Syndrome?
Direct Proton Pump Inhibitors
What are the different types of Peptic Ulcer diseases?
Gastric
Duodenal
Oesophageal
Which drugs for Peptic ulcer diseases gives an indirect inhibition of acid secretion acting as an H2 antagonist?
Cimetidine
Ranitidine
Famotidine
Nizatidine
Take H2 blockers before you DINE. “Think “table for 2 when you dine” to remember H2.
Which set of drugs are known as Coating Agents ?
Bring - Bismuth subsalicylate
Such - Sucralfate
Man- Misoprostol
” Bring Such Man Coat “
Why are Antacids not the best treatment in Peptic Ulcer diseases?
They can produce foaming leading to acid reflux
Antacids are usually given at a dose to obtain pH > 4
An increase in pH can stimulate gastrin secretion which is not good because Gastrin can increase acid secretion and GIT motility.
What is the Mechanism of Action for H2 receptor antagonists?
They act by COMPETITIVE inhibition of H2 receptors causing decreased cAMP activation of H+,K+-ATPase therefore decreasing acid secretion.
Where is the site of action for Proton pump inhibitors drugs?
Cancaliculi of parietal cells
What is the mechanism of Action for Proton Pump Inhibitor Drugs?
Irreversibly ( permanently) inhibit H+/K+ATPase in stomach parietal cell
What are examples of Proton pump inhibitor drugs?
Omeprazole (Prilosec)
Lansoprazole
Esomeprazole (Nexium)
Pantoprazole
Dexlansoprazole
Raberprazole (Aciphex)
“The Prazoles”
True or False? Proton pump inhibitors will cause an increase the pH of the stomach in which a higher gastric pH will cause increased gastrin release via a feedback loop. Long-term use of PPI’s has been associated with pneumonia and enteric (including C. difficile) infections.
TRUE!!
Fill in the blanks. “ Proton pump inhibitors are converted to ________by acid medium.”
Sulfenamide
What is a clinical significance when taking Proton Pump inhibitors?
These drugs should always be given a coat so that it does not get destroyed by acid - patient must not cut tablets as it must stay in capsule. When these drugs are converted to Sulfanemide in an acid medium it doesn’t pass the membrane readily and MUST stay in the prodrug form!!
True or False? H2 receptor antagonists promote a longer healing time than Proton pump inhibitors.
FALSE!! PPI’s promote a longer healing time of stomach
When should PPI’s be taken?
15-30 mins before meals
Which drug belonging to the Proton Pump Inhibitor drug group is not eliminated by the liver enzyme - H CYP2C19/ 3A4?
Raberprazole ( Aciphex) - This is beneficial so it can be used in patients taking other drugs .
What is the mechanism of Action for Misoprostol?
It increases the inhibitory activity via prostanglandin E1 (PGE1) receptor. It acts on the receptors on superficial epithelial cells to increase mucous and bicarbonate production.
True or False? Misoprostol also decreases the histamine effects and ultimately decrease acid secretion at higher doses?
TRUE!!
Which drug that is classified as a coating agent is mainly used in NSAID- induced peptic ulcers (
Misoprostol
Which drug that is classified as a coating agent has an antibacterial effect against H pylori by inhibiting urease?
Bismuth Subsalicylate ( Peptobismol)
What is the Mechanism of Action for Bismuth Subsalicylate?
It enhances secretion of mucus and HCO3.It accumulates and coats crater of ulcer.
Which coating agent should not be given with an Antacid, PPI’s or H2 receptor antagonists?
Sucralfate - Antacids prevent activity
What are the antimicrobial used to eradicate Helicobacter pylori?
M - Metronidazole
A - Amoxycillin
C- Claritromycin
Which anti- emetic drugs are H1 antagonists?
PROMETHAZINE
CYCLIZINE
DIMENHYDRINATE (gravol)
” pcd are H1 antaginists’
What is the mechanism of action for H1 antagonists (Anti-emetic drugs)?
Competitive antagonist - H1 receptors in vestibular nuclei & VC
Which antiemetic drug is a M-antagonist?
Hyoscine
” H& M”
What is the MOA of Hyoscine?
Antagonist of M receptors in vestibular nuclei & VC.
Most useful for prevention of motion sickness.
Which anti-emetic drugs are a 5HT3 receptor antagonists?
Granisetron
Tropisetron
Ondansetron
Dolasetron
” Grani Tod are 5HT3 receptor antagonists” - The Setrons
What is the MOA of 5HT3 receptor antagonists?
Blocks 5-HT3 receptors in visceral afferents & CTZ
What are the adverse effects of 5HT3 receptor antagonists?
- Headaches (Overdose only results in headaches) * Constipation (bloackade of GIT motility associated 5HT4)
- Cardiac irregularities (QT prolongation
What drugs are D2 antagonists with CNS Adverse effects?
Proclorprenazine
Clorpromazine
” Prone to adverse affects of Cns “
What are the CNS adverse effects of D2 antagonists?
Antimuscarinic, antihistaminergic , sedation, postural hypotension.
EXTRAPYRAMIDAL SYMPTOMS - muscle rigidity, muscle tremors, restlessness, involuntary movement
Which drugs are D2 antagonists that don’t have any CNS adverse effects?
Metoclopramide
Domperidone
True or False? Metoclopromide has a greater efficacy than domperidone.
FALSE!!
Fill in the blanks. “ An anti-emetic drug that is also a steroid is ___________.”
Dexamethasone
Which anti-emetic drug is a NK1 antagonist?
Aprepitant
Which drug should be given to a patient experiencing nausea / vomiting in pregnancy?
Dietary, H1 antihistamines
Which drug should be given to a patient with Postoperative nausea and vomiting?
Ondersetron,Metoclopromide
Which drugs are examples of Cannabinoids?
Dronabinol
Nabilone
What is the MOA of Cannabinoids?
They interact with CB1 R on STN to inhibit serotonin release.
What are the different types of Laxatives?
Stool softeners
Bulk (12-72 hours)
Osmotics
Stimulants
Which laxative drugs are Osmotics?
Magnesium sulphate (Epsom salts)
Magnesium Hydroxide (milk of Magnesia)
Which laxative drugs are Bulk?
Bran
Pysllium (Metamucil)
Methycellulose (Citrucel)
Which laxative drugs are stool softeners?
Docusate
Glycerin
Mineral oil
Which laxative drugs are stimulants?
Castor Oil
Bisacodyl
ANTHRAQUINONE DERIVATIVES: CASCARA, SENNA
Which laxative drugs require water intake?
Bulk and Osmotics laxatives
What is an adverse effect of the drug Senna(stimulant laxatives) ?
Senna long term use may result in melanosis of the colon
Which Anti-diarrhoeal drug is a somatostatin analogue?
Octreotide
What is the MOA of Octreotide?
Stimulates somatostatin receptors to result in inhibition of GIT related hormones secretions (e.g. secretin, gastrin, VIP)= decrease motility
Which anti-diarrhoeal drugs causes bulking of the stool?
Kaolin
Pectin
Which anti-diarrhoeal drugs are Opiates?
Diphenoxylate
Loperamide
What is the mechanism of action of Opiates ( Anti- Diarrhoeal drugs) ?
Stimulate presynaptic µ opiate receptors in the myenteric plexus to reduce Ach release and therefore decrease peristaltic activity. Also reduces pain.
Which anti-diarrhoeal drug can be used for Traveller’s diarrhoea?
Bismuth Subsoilcylate
Which drug is a monoclonal antibody for tumour necrosis factor alpa (TNF- alpha)?
INFLIXIMAB
Which drug in the treatment of IBD is anti-inflammatory and binds to steroid receptors in cells to suppress expression of genes associated with the synthesis of cytokines: Il-1, IL-2, TNF-α, interferon-α,?
BUDESONIDE
Which drugs in the treatment of IBD are Cox inhibitors?
Sulphasalazine
Mesalamine
Which dug is a prodrug activated by bacteria and reaches the small intestine intact?
Sulphasalazine
